Conversion of reciprocating motion to rotary motion and vice versa, in cycle-operating parameters, particularly, reciprocating internal combustion engines, has been known for many years and numerous arrangements for conversion of reciprocating motion of a piston, to rotary motion of a crankshaft has been proposed. Besides the conventional arrangements that include pistons, connecting-rods and crankshafts, further, it has been proposed in several ways, to utilize an internally or externally teethed roller-gear, attached to a single or dual-headed pistons, to be engaged with a circular-gear, externally teethed and fixedly mounted on a drive shaft.
What distinguishes one such proposal from the other and consider the key to every such invention, chiefly is the system with which a roller-gear and a circular-gear are constantly engaged. Matters to be considered in such gear engagement systems include:
a. consistency between the moving parts from the engineering points of view;
b. efficiency in conversion of maximum energy;
c. fluency in motions, particularly as the circular-gear shifts from one side of the roller gear to the other; and
d. simplicity.
Engagement of a roller-gear and a circular-gear in the prior art, typically proposed to be assisted by a secondary gear engagement system, designed specifically to maintain constant engagement of the roller-gear and the circular-gear. Such gear engagement systems in general, either having complex embodiment involving numerous moving parts, or not properly functional, due to inconsistency between the moving parts and poor engineering design. Lack of said major requirements, perhaps is the reason as to way such proposals are yet to be accepted as a superior alternative to the conventional crankshaft and connecting-rod systems. Examples of such arrangements, are shown in U.S. Pat. Nos. 1,316,437 to Flood, 4,395,977 to Pahis, 4,608,951 to White, 4,864,976 to Falero and 4,941,396 to McCabe.